Equations

Accessible equations are currently supported only in Word 365 and not Office LTSC. See our knowledge base entry on converting your document to PDF for more information about issues with Office LTSC.

Equations should be integrated into the text of your disquisition and not grouped at the end of a chapter. Display equations should be separated out of the body text onto a new line, whereas in-line equations may be included within body paragraphs, non-text item titles, tables, and etc. as long as they use Unicode characters in the same font as the paragraph text. If an equation interferes with line spacing, such as a fraction in bar notation, it may need to be formatted as a display equation. Examples of formatted equations with an equation number can be found in our disquisition templates.

If you use a large number of equations in your disquisition, you should consider including a List of Equations in the prefatory material. Unless otherwise directed by the style manual of your discipline, including a List of Equations is optional. In the List of Equations, a brief title or description of the equation should be included in each entry. However, equations in the document chapters should not be given a title, and the equation should be described in your text. See our knowledge base entry on prefatory lists for our full guidelines, including instructions on making a List of Equations from scratch.

Guidelines: Equations

  • Equation position – Display equations should be on their own line, centered on the page. (With 1" margins, the center of a page is at 3.25".) Equations, like these, that are separate from your text are referred to as "display equations" in our guidelines, as opposed to in-line equations within text.
  • Numbering is optional – When you use display equations in your disquisition, you may number them to make it easier to reference them within the text. If you number any equations, then you should number all equations; if your disquisition contains proofs or series of equations, you may elect to number only the final step or product. If you include a List of Equations, only numbered equations should have entries.
  • Number position – If a display equation is numbered, the equation number should be flush with the right 1" page margin.
  • Number sequence – Equation numbers should be sequential. You can number the equations ordinally by appearance in their chapter (such as 1.1, 1.2, 1.3, 2.1, 2.2, 2.3, etc.), or you can number them ordinally by appearance in the document (such as 1, 2, 3, 4, and so on).
  • Number label – Equation numbers must be enclosed in parentheses: "(1)". You may optionally include the label “Equation” or “Eq.” in the parentheses before the equation number: "(Equation 3.2)" or "(Eq. 3.2)". If you include a label for an equation number, all equation numbers should use the same label.
  • Font: display equation – Display equations should be in the same font as the paragraph text or use a different font, such as Cambria Math. All display equations should use the same font.
  • Font: equation number – If a display equation is numbered, the number should be in the same font as the paragraph text.
  • Font: in-line equations, etc. – In-line equations, variables, symbols, or functions outside of display equations should use the same font as the paragraph text; this includes includes operators and numerals. In-line equations, variables, symbols, and functions in paragraph text, titles, notes, or tables should be Unicode characters.
  • Alt-text – Equations should be tagged as <formula> and have alt-text that describes it.
    • Note that alt-text cannot be directly added to Word equations, but may be automatically generated when you convert your document to PDF. See our equation accessibility requirements and the related issue on this page for more information.

Requirements:

  • Equations, expressions, and formulas should be tagged <formula>. (WCAG 1.1.1)
  • In-line equations, variables, symbols, or functions outside display equations that use non-Unicode characters should be tagged <formula>. (WCAG 1.1.1)
  • All <formula> tags should have natural language alternative text that describes their purpose/function. (WCAG 3.1.2)

Resolution:

  • In a PDF editor, add natural language alt-text to <formula> tags that describes the equation.
    • Some versions of Word will add automatically generated alt-text to <formula> tags, but automatically generated alt-text may be insufficient to accurately describe an equation. Review the alt-text of all <formula> tags and revise as necessary to be parseable.
    • We recommend nesting a <P> tag within each <formula> tag, then add natural language alt-text to the <P> tag's Actual Text attribute. This is necessary for some screen readers to parse formula tags. See the guide "Adding Alt-text to Formula Tags" below for more information.
  • Use Unicode characters in display equations as well as in-line equations, variables, symbols, functions, etc. in paragraph text, titles, notes, tables, etc.
    • Our Word templates come with the XITS font pre-installed, and equations created in our Word templates default to Unicode characters. You may also add symbols from the Insert tab -> Symbols menu, and set properties like italics or subscripts within their font settings.

Equations created in Office LTSC are missing required accessibility features and may not be rendered correctly. See the issue entry "Equations Created in Office LTSC" on this page and our knowledge base entry on converting your document to PDF for more information about this issue.

A list of PDF editors available to you on campus and remotely can be found in our knowledge base entry on digital accessibility.

Tutorials:

Video: Tagging a PDF

Text: Adding Alt-text to Formula Tags

  • OfficeMath is the default equation editor packaged in Word (and other Office applications).
  • MathCast is an open-source standalone equation editor that can export MathML equations to Word or LaTeX. It is free to use.
  • MathType is an add-in for Word available in the Office Store. It has a 30-day free trial and requires a subscription thereafter.
  • Mathpix is a suite of web, desktop, and mobile apps that can import or export equations for LaTeX, with support for Markdown rendered equations. It has relaxed usage limits for .edu accounts, and requires a subscription otherwise.
OfficeMath: Word

OfficeMath is included in all Word distributions. Add equations to your document from the Insert tab -> Equations menu or hotkey ALT+=. OfficeMath equations use a MathML analog called OMML, and equations created in Word 365 will be converted to PDF with automatically generated alt-text built from OMML. See our knowledge base entry on converting your document to PDF for more information about issues with equations in Office LTSC.

MathCast: Word & LaTeX

MathCast can be downloaded from its homepage. Run the program, and use its equation editor to build your equations. Before exporting any equations, change the clipboard copy type to MathML under Edit -> Settings. Do not export images into your document. MathCast will automatically generate alt-text for formulas, but like all automatically generated alt-text, it may not be in natural language and may require editing.

MathType: Word

MathType should be installed from the Office Store. Navigate to the Insert (or Developer) tab and select Add-ins to open the Office App Store; search for MathType and install it. To create equations, open MathType from the MathType Add-in tab and use the built-in equation editor. When converting to PDF, MathType will automatically generate alt-text for formulas, but like all automatically generated alt-text, it may not be in natural language and may require editing. See the MathType website for documentation.

Mathpix: LaTeX

Mathpix can be accessed from its homepage.

Quick Answers

Yes. While display equations should be centered on their own line, in-line equations, variables, symbols, or functions can be included within paragraph text, titles, tables, etc. with some restrictions.

First, the in-line equation should not affect the line spacing of the content; for example, a tall equation should be excluded or reformatted to fit, and equations with divisors should use solidus notation. Second, the equation should be in the same font as the paragraph text. Third, these equations must use Unicode characters or otherwise be machine-readable, and alt-text is still required for in-line equations.

Do not use the Word equation editor for equations in paragraph text, titles, tables, etc. Instead, use the Insert -> Symbols menu for special characters and format scripts using font settings. Alternatively, use MathCast or MathType to create accessible MathML equations.

Numbering equations is optional, but if you choose to number equations then all equations should be numbered. However, some exceptions may be made. For example, if you have a series of equations that demonstrate how another equation is derived, numbering only the final equation makes more sense: it helps set it apart, and may be the only equation in the series that will be referenced elsewhere.

No; the List of Equations is optional. However, we recommend making a List of Equations whenever you reference equations across multiple pages or sections or if you have a large number of equations. Like a List of Abbreviations or List of Symbols, having a List of Equations improves your reader's experience navigating and referencing your document. The list of Equations should follow the general formatting of other prefatory lists.

Issue: Equations or Their Numbers Misaligned

Requirements:

  • Equations should be centered on the page; with 1" margins, the center of a page is at 3.25" on the ruler.
  • If an equation is numbered, the equation number should be flush with the right 1" page margin.

  • Under paragraph settings, add a tab stop at 3.25" for equations and 6.49" for equation numbers.

Without a number, equations can be easily centered by using the alignment tool on the Home tab (hotkey CTRL+E). If your equation is numbered, use the steps and settings below to place a centered equation and right-aligned number on the same line.

  1. Place your cursor on the line with the equation, but outside of the equation editor.
  2. Open the paragraph settings for this line and use the following settings, also shown in the image below.
    1. Alignment: left
    2. Line spacing: single, with 0 pts before and 12 pts after
  3. Click the "Tabs" button at the bottom left of the paragraph settings dialog box to open the tab settings for the line. In the tabs settings dialog box, apply the following settings for two tab stops, also shown in the images below. After entering the settings for each tab stop, click "set" to save the settings.
    1. Position: 3.25", alignment: center, leader: none. This is the tab stop for the equation.
    2. Position: 6.49", alignment: right, leader: none. This is the tab stop for the equation number.
  4. Place your cursor in front of (to the left) of the equation and press the Tab key to move it to the first tab stop, centering it.
  5. Place your cursor in front of (to the left) of the equation number and press the Tab key to move it to the second tab stop, placing it against the right margin.

You can copy these formatting settings to other equations quickly using the Formatting Painter tool and its associated hotkeys. Do not use a table to align equations, or any other content, on the page; if you do, you will need to remediate the table in a PDF editor after converting your document. Furthermore, while the formatting above can be easily replicated across all display equations using the format painter, using a table requires you to repeatedly copy and paste multiple elements.

Paragraph and tab stop settings in Word for equations and equation numbers.

Issue: Inconsistent Equation Font

Requirements:

  • Display equations should use a consistent font.
  • In-line equations, variables, symbols, or functions outside of display equations should be in the same font as the paragraph text.
  • Equations, expressions, and formulas should be tagged <formula>. (WCAG 1.1.1)
  • In-line equations, variables, symbols, or functions outside display equations that use non-Unicode characters should be tagged <formula>. (WCAG 1.1.1)
  • All <formula> tags should have natural language alternative text that describes their purpose/function. (WCAG 3.1.2)

Resolution:

  • Install the XITS Math fonts.
  • Use the XITS Math font for all display and inline equations.

Inline equations should always be in the same font as the paragraph text, whereas we recommend but to do not require matching the font of your display equations to the font of your paragraph text. Equations in our Word and LaTeX templates use the XITS Math font by default to match the default Times New Roman paragraph text. Since the default equation font has the same appearance as the paragraph text, equations made with the XITS Math font may be used within paragraph text, tables, titles, etc. See below for instructions on installing the XITS font.

Install the XITS font

If you do not have the XITS font installed, you can download it from its GitHub repository by clicking the green "Code" button and selecting "Download ZIP". To install the fonts, open the ZIP file and double-click the xits-math.otf file, then click "Install" in the font dialog box; repeat for xits-mathbold.otf. In addition to the math-type fonts, we recommend installing all XITS fonts included in the package.

Removing Inconsistent Font with "Replace All"

You can use the Find & Replace feature in Word to quickly replace equation fonts, which is especially useful for changing equation fonts after installing a matching font.

  1. Open the tool from Home tab -> Editing Group -> Replace or press Ctrl + H.
  2. Click in the "find what" field to place your cursor there.
  3. In the Find and Replace dialog box, click More >>.
  4. Click Format -> Font at the bottom of the dialog box.
  5. Select the font you want to replace in the Find Font dialog box and click OK.
  6. Click in the "replace with" field to place your cursor there, and repeat steps 4 & 5 for the font you want to change the old font into.
  7. Click "replace all" in the Find & Replace dialog box to change all the text with the undesired font into the desired font.

See the image below for an example of the Find & Replace dialog box with advanced settings shown. In this example, all "Cambria Math" fonts would be replaced "XITS Math".

Resolution:

  • Use the OfficeMath equation editor for display equations only.
  • Use Unicode characters from the Insert -> Symbols menu to build in-line equations or reference variables, symbols, functions, etc. outside of display equations.

We recommend installing a matching font for your equations, such as the XITS Math font to match Times New Roman. However, if you do not want to install an equation font that matches your paragraph text font, cannot find a matching font, or would prefer to use a different font for your display equations as a matter of style, you are welcome to do so. Your equations should still follow our requirements for consistent font.

Display equations should all use the same font. Explanatory or supporting text with your display equations may use the same font as the equation itself or the paragraph text--choose one style and apply it to all display equations. If there are more than a few words of explanatory or supporting text with a display equation, that text should be in the same font as the paragraph text.

In-line equations, variables, symbols, or functions outside display equations--such as in the paragraph text or a figure title--should be in the same font as the paragraph text, and should use Unicode characters. Numerals and operators outside of equations should always be in the same font as the paragraph text. Special symbols can be added to your text from the Insert -> Symbols menu, and these symbols can be formatted directly from the text's font settings, such as superscripts or subscripts.

Ex.: Two acceptable font schemes for an equation when using a non-matching equation font. (Note: non-italicized text indicates paragraph font and italicized text indicates equation font.)

Y = Mx + B, for all x (1)

r2= x12 + x22, for all x (2)

In eq. 1, the text "Y = Mx + B" and "x" is in the equation font, whereas the text "for all" is in the paragraph font. In eq. 2, all of the text is in the equation font; because there is little supporting text, it can be in the same font as the paragraph text. We recommend the formatting for eq. 1, but the formatting for eq. 2 is acceptable. You may need to manipulate the formula tags for equations styled like eq. 1 to ensure the alt-text uses natural language.

The find and replace dialog box with advanced options shown

Issue: Alt-text Required for Equations

Requirements:

  • Equations, expressions, and formulas should be tagged <formula>. (WCAG 1.1.1)
  • In-line equations, variables, symbols, or functions outside display equations that use non-Unicode characters should be tagged <formula>. (WCAG 1.1.1)
  • All <formula> tags should have natural language alternative text that describes their purpose/function. (WCAG 3.1.2)

  • Use the Word equation editor (with the XITS font) to create equations in Word 365 (do not build equations in Word LTSC--see this DQKB entry for more information on Word 365 vs. LTSC).
    • When converting to PDF, OfficeMath will automatically generate alt-text for an equation's respective <formula> tag ; review & verify that this al-text is human-parseable and accurate.
  • Alternatively, use a PDF editor to add a natural language description of the equation into the Alternate Text field. Additionally, Adobe recommends nesting a <P> tag in the <formula> tag and copying the alt-text into the Actual Text field of the <P> tag.
  • Reduce the number of equation objects requiring alt-text in your document. In Word, Unicode symbols can be found in the Insert -> Symbols menu and used to build in-line equations or reference variables, symbols, functions, etc. outside of display equations. Unicode characters created in this way do not generally require alt-text.

Do not create OfficeMath equations in Word LTSC; see this DQKB entry for more information on Word 365 vs. LTSC. If you do not have access to Word 365, use the Insert -> Symbols menu for all in-line equations and variables, symbols, or functions outside display equations. When you reach the remediation phase of your publication review, use a PDF editor to add natural language alt-text to any display equations.

Alt-text for equations should be in natural language and descriptive. For example, given equation 2,

r2= x12 + x22, for all x, (2)

some options for alt-text may be:

  1. "r squared equals x sub 1 squared plus x sub 2 squared, for all x", or
  2. "the square of r is equal to the square of x sub 1 plus the square of x sub 2, for all x", or
  3. "the sum of variable x sub 1 squared plus x sub 2 squared is equal to r squared, for all x".

This alt-text is read aloud by the screen reader in place of the equation. Alt-text automatically generated by MathType, Mathpix, or other MathML converters will likely require some adjustment. Word 365 naturally supports a MathML analog (called OfficeMathML), whereas Word LTSC does not; as such, equations created in Word LTSC will produce <formula> tags in your PDF that require alt-text to be added manually.

Tutorials:

Center for Writers

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